RAM Double Ball Yoke Clamp Mount for Garmin GPSMAP 176, 396, 496 + More (RAM-B-121-GA7U) (sku 54223)The RAM B 121 GA7U consists of a yoke clamp base, double socket arm and cradle for the Garmin GPSMAP. The RAM yoke clamp mount will fit rails from 0. 625" to a maximum of 1. 25". Designed into the mount is a 1" diameter patented rubber ball and socket system with adjustment points at the base and cradle. With a twist of the arm knob, you can move the yoke clamp mount to your optimum viewing position. HARDWARE INCLUDED Assembly Hardware CLAMP RANGE .